what is the setup of the other units other than the 6 without issue? like are they using wifi or not? how about content like images and videos - are they all of the same resolution, dpi, quality/compression setting (the file size would indicate their differences - for video, divide the file size with the number of seconds).
it looks like it has more than one issue - if the player goes red, it indicates the player is going offline which can be that the content you have may be causing issue. if its toggling between yellow and green, its more likely that its the content also. we however are not discounting there are issues with the network as well.
it would be best to join us on chat so we can troubleshoot the issue faster. join us at
http://chat.digitalsignage.combest regards
-ADMIN